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Stimuli-responsive polypeptide vesicles by conformation-specific assembly.

Enrico G Bellomo·Michael D Wyrsta·Lisa Pakstis·Darrin J Pochan·Timothy J Deming
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Abstract

In biology, lipids are well known for their ability to assemble into spherical vesicles. Proteins, in particular virus capsids, can also form regular vesicle-like structures, where the precise folding and stable conformations of many identical subunits directs their self-assembly. Functionality present on these subunits also controls their disassembly within the cellular environment, for example, in response to a pH change. Here, we report the preparation of diblock copolypeptides that self-assemble into spherical vesicular assemblies whose size and structure are dictated primarily by the ordered conformations of the polymer segments, in a manner similar to viral capsid assembly. Furthermore, functionality was incorporated into these molecules to render them susceptible to environmental stimuli, which is desirable for drug-delivery applications. The control of assembly and function exhibited in these systems is a significant advance towards the synthesis of materials that can mimic the precise three-dimensional assembly found in proteins.

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Hydrogen-Ion ConcentrationLipidsModels, ChemicalMolecular ConformationPeptidesPolymersProtein ConformationProtein Structure, TertiarySpectrometry, FluorescenceStereoisomerismJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Enrico G Bellomo, Michael D Wyrsta, Lisa Pakstis, Darrin J Pochan, Timothy J Deming. 2004-03-14. Stimuli-responsive polypeptide vesicles by conformation-specific assembly.. https://doi.org/10.1038/nmat1093

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